Cinematograph film material



Aug. 7, 1928.

J. E. THORNTON CINEMATOGRAPH FILM MATERIAL Original Filed May 5, 1924 COLORED CoLLolD Suas-RA TUM BLUE vloLE-r ORANGE YELLOW BLUE GREEN '.Patente'd. 7,1928. I l I UNITED STATES 1,679,695 im'rilslsx'rl oFFcE.

JOHN EDWARD THORNTON, OF WEST HAMPSTEAD, LONDON, ENGLAND.

CINEMATOGRAPH FILM MATERIAL.

Original application illed May 5, 1924, Serial No. 711,255, and in Great Britain May 1'8, 1923. Divided and -this application iiled Octoberl, 1925. Serial No. 66,050.i

This invention` relates to film material for I the production of transparent multi-color cinematograph film-positives in four or three colors. y .t

5 In the specification of m U. S. application Serial No.` 711,255, file' May 5, 1924, of

which this application is a division, I have described a four-color cinematograph {ilmpositive built up' from four differently-col- 1o ored component images, which are formed in four differently-colored colloid layers, a separate color upon each side of two strips of thin celluloid support; the-two strips with their four images being cemented together after printing and iinishing, to form a single compound film-strip of four-color pictureswhich are produced by the superimposition and combination of the four component images within the space-of one-picture-area, the assembled complete picture comprising one image` on the front, .two in the centre, and one on the back of the' film.

In the specification of my U. S. applica-J tion Serial No.y 60,348, led October 3, 1925,

I have described a form of lfilm-material comprising a double-width support of celluloid, with two parallel stripes of colored colloid attached to the front and two on the back of the support, all four stripes being of dierent colors,- and also with a layer of soluble removable 4light-obstructing material placed between the 'colored stripes in order that the two sides ofthe sensitive lm can be simultaneously printed without the light l from one side penetrating .to and yspoiling the print on the other side. U

In the present invention a film-material similar to the above is provided but with the difference that the light-obstructing lay- 4()4 er is omitted, so that -the light can penetrate in order to form two prints' by the method hereinafter described. L

In the Specification of my U. S. application Serial No. 60,349, filed October 3, 1925,

v I have described methods of manufacture equally applicable to both ,kinds of filmmaterial described fin the application 4Sle-v rial No. 60,348, filed October 3, 41925, and' in` the present application. 5o .This invention therefore consists of l a ready-colored film-material (either readysensitized or adapted to be sensitized by the user) comprising a strip of Celluloid or other .waterproof material of double standard -width and half lstandard thickness and a ary 15, 1924, 224,571, dated May 18, 1923, d,

and 224,572, dated March 18, 1923,1n which the colors are interspersed as they are in the well-known autochrome plate, and printing is eiected by using only the one negative by printing from only one side of the film,`

by making two successive exposures, through differently-colored lighty iilters, so that only one color-component of the negative is printed von the sensitized front at one eX- posure and t-he other color printed on the sensitized back (through the front `sensitized layer'and its cut-out filters) at the other exposure.

In this Icase therefore one of the color prints is formed upon the front of the film in `dots or lines, and the other color-print is formed upon the .back of the film in dots 'or lines that fall in the spaces between those formed upon the other side of the film:

The invention will be described with reference to the accompanying drawing where- 1n:

`Fig. 1 is a perspective view of a film embodying the invent-ion; and f Fig. 2 is a cross-section of the film shown irlig. 1, transversely of the length of thel The hlm-materialis manufactured with a transparent centra-l base of Celluloid (or similarwaterproof material) of only' about .00100 inch thick, and of double standard width so that all the four'section-images can be printed, developed, and dried simultaneously to secure uniform density and color balance in all images and also to ensure uni-. formexpansionand contraction. When the double-width print is finished and driedl it is slit into two separate strips. The colored colloid consists of gelatine, albumen, fishglue or the like with which suitable dyes or other coloring matter is incorporated.

To bothy sides of the thin do'uble'width'V material an adhesive substratum of the usual type is applied, of about .00005 inch in thickness (though it may be thinner) land upon this both sides are coated with a layer of colored colloid, arranged as two parallel stripes of different colors upon eachside (four stripes in all) which run longitudinally of the film. These layers are pref'- erably made about .00090 inch thick each,

but maybe slightly more or less. rllhe adhesive substratum serves to indissolubly unite the coloredfcolloid stripes to the cenl tral transparent waterproof' base.

-sensitized with salts of' silver.

The colored layers require to-be sensitive to light, and may be sensitized by various processes, for example In one method the colored film may be stored in a non-sensitive condition and is rendered sensitive by the printer .immediatelybefore use by treatment in a bath of a suitable bichromate salt and then drying. When such film is exposed under a negative or positive the colloid is rendered insolublein parts, and at those points the coloring matter is permanently locked up with thev be applied as a bath in the same way as the salts of bichromate or iron, as used in welli known print-out processes.

In another method the film-material isl sensitized vby the film-maker and can be kept stored for a long period in its sensitive condition and is always ready for immediate use by the printer. In this case the colored colloid and silverl salts,are formed into an emulsion, as in the well-known gelatinosilver-bromide or gelatine-silver chloridel vprinting processes.

In whichever of these methods is adopted for rendering the colored colloid sensitive to light, the necessary coloring matter is incorporated with the' colloid at the time of manufacturing@ the. film, and the coloring matter not required in the image is Awashed out or removed from the colloid by suitable re-agents after printing and developing.

The coloring matter used in forming the image itself can be rendered 'still'more per-- manently fixed by the application of-'suitable mordants, all in manner well-known.

The methods of printing a. film sensitized according to any of the different sensitizing processes, and the different treatment required in the kdeveloping,`and other processes after printing, are all well-known to those vacquainted with 'each process;l they form no art of the present invention and are therefbre -notdescribed in detail herein..

These may Y Atreatment of all four sections of For' a four-color film the colors preferred are crimson-red, blue-green, orange-yellow, and blue-violet, but these colors may be slightly modified if desired.

The colored vcolloid is applied toV the double-width strip of transparent waterproof base or support in the form of two parallel stripes of two dierent colors upon one side of the support and two parallel stripes of two other colors upon the other side of the support.

The film-material is intended for its front prints to be made direct on to its front colored stripes, and theback prints to be made indirectly upon its back colored stripes, by exposing the back stripes through the front ones and through suitable cut-out color filters. By this means prints are made from one double-width negative which comprises four color component images of' the screenfilter type as described in my British Patents NoS. 233,989, dated February 15, 1924, 224,571, dated May 18, 1923, and 224,572,

dated May 18, 1923, by two exposures alternately through the one negative; the first exposure printing the colored stripes on the n back of the film through the.- colored stripes on the front and through filters which cut out the other color and protect from exposure the front layer whilst the back layer is being printed; after which the front layer is printed at the second exposure with the cut-out filters removed.

- It is therefore preferred to place the red and green colored colloid stripes backI to back and the yellow and violet back to back,

so that the front and back colored "stripes .l

printing' through in double-width negatives of the type described, all four images can be printed simultaneously 'and automatically at., one printing operation without the necessity of a large amount of highly skilled labour,

and the various subsequent operations ofdeveloping, fixing, washing, mordanting, colorremoving, or the like can also be effected by automatic machinery that Iwill ensure equal picture.

Moreover the use of ready-colored filmmaterial made according to this invention obviates the uncertainty of result and great expense in adjusting the colors which wouldy be necessary if non-colored sensitized film were used and the four images colored after development by the known Aprocesses. of dyeing for each color separately. Also a morelcertain qualityof result lis obtained, owin to the coloring matter for each-section ing incorporated with the sensitized layer at lthe time of its manufacture in exact the same.-

the invent-ion is not restricted thereto but will be found equally applicable to and is intended to be used in other multi-color photography (non-cinematograph).. l

Although the complete iilm is herein described as a double-width strip, it may for convenience and economy in manufacture be formed as a wide web of several strips, as usual in manufacturing most sensitized material, the web being slit into a number of double-width strips afterwards.

Although the coloring matter can be incorporated with the colloid mixture before the film support is coated as strips, I prefel` the following method of manufacture.`

The wide web, or alternatively the doublewidth strip, is irstcovered all over upon both sides bya suitable coating machine with non-colored colloid, eitherot the readysensitized or non-sensitized variety. After drying it is next passed through a machine whichapplies the solutions of coloring matter or--dyesin the form of colored strips each vbeing the width of a single film. These solu- -tions are each adjusted -to t-lie correct strength or intensit of color vand are applied until the colloid i's charged to satura- A tion and the colors have penetrated the entire thickness of colloid down to the waterproof base ,or support.

If necessary the colors may be .mixed with a mordant; or the mordant may be incorporated with the colloid before the colors are applied; or the ymordant may be applied last' of all, after coloring.

A The webA or strip is dried! andis then ready for use. l' j at I claim as my invention and desire protect by? Letters Patent isz-#- 1. For the production of multi-color ietures in which fourimagesof different co ors are formed u on a single transparent support of double width by printing alternately upon the `two sides by two separate succeeding exposures, then' developing, finishing, severing into two parts and subsequently superim osing and cementing the two parts; a

mu tiI-color cinematographnor other L sitive film-material, comprising a 'strip o transparent waterproof support of double width vand half thickness, a first layer of colored colloid in twoparallel differently-colored stripes upon one side of the supportand a secondlayer of colored colloid in. two paral lel differently-colored stripes upon the other #side of the support, and an adhesive sub- `stratum layer between each colloid layer and its support without a light nobstruetinff layer.

2. For the production of multi-co or icturcs in which four images of different co orsa are formed upon a single transparent support of double width by printing alternately l upon the two sides by two separate succee ing exposures, then developing, imshing, severing into two parts and subsequently superimposing and eementin g the two parts;l i a multi-color cinematographv or other posxtive film-imiterial, comprising a strip of transparent waterproof support ol double u width and half thickness, a first layer of colored colloid in two parallel differentlycolored stripes upon one side ot' the support and a second layer of colored colloid in two parallel dill'ereitly-colored stripes upon the other side of the support, the colored colloid layers being sensitized, and an adhesive substrat-1.1m layer between each colloid layer and its support without a light obstructing layer.'

3. For the production of multi-color 1ctures in which ilour images of different co ors are formed upon a single'ti'ansparent support ot doublenqwidtlrby'printing alternate y upon the twi'sdcs by two separate succee ing exposures, then developing, finishing, severing into two parts and subsequently siiperiinposiug and cementing the two parts; a multi-color cinematograph or .other positive film-material compris-ung'K a strip of waterproof su ip'ort approximatel .00100 inch thick; a layer of ladhesive su stratum approximately .00005 inch thick applied to cai-.h side of the support; a layer of sensitized colored colloidy approximately .00090 inch thick in two stripes-on each siibstratum layervbut without a light obstructing layer, the two stripes of colloid on one side of said support being colored differently from thosel on the opposite side of said support.

`4."'For the production of multi-color pictiii'es in X which four images of 'dilerent colors are formed upon a single transparent support of double width by printing alterj nately upon the two sides by two separate sucweding exposures, then developing, linishing, severing into two parts and'subse'- quiently super-imposing and cementing the two parts; a multi-color cinematograph or other positive film-material of Adoublewidth comprising a central waterproof support having two di'erentl-colored parallel stripes of sensitized co loid on each side thereof but without a light obstructing layer, the two stri es of colloid on one side ofsaidv support eing colored differently .from those on the opposite side o f said support. y

In testimony whereof I have hereunto set my hand.

` JOHN EDWARD THORNTON. 

